This morning, astronaut Chris Cassidy looked out the window of the International Space Station. He saw the usual thing -- the vast expanse of the visible cosmos, unimpeded by the Earth's blurring atmosphere -- and then he saw a thing that was less usual. A bright thing. A vaguely spherical thing. A thing that was floating near the Station's Progress cargo vehicle. The strange object looked like a jellyfish floating in the sea of space. In the darkness, it glowed yellow-orange. Cassidy called down to Mission Control in Houston. And then he took out his camera. He began filming.